Studying the biology and epidemiology of oncogenic viruses such as Kaposis sarcoma associated herpesvirus (KSHV), also known as human herpesvirus 8(HHV-8) will help us to understand the pathogenesis of cancers caused by viruses. Laboratory techniques in molecular biology and immunology are rapidly advancing and the Viral Epidemiology Laboratory aims to find new ways to exploit such advances in an epidemiological setting.KSHVBoth serological and molecular methods for identifying KSHV infection in asymptomatic individuals are problematic. We have evaluated many assay combinations and are using the best currently available assays for epidemiological studies of KSHV infection and disease. Major questions in KSHV epidemiology include why there are such striking geographical differences in the prevalence of KSHV, what are the routes of transmission of this virus and what are the risk factors for KSHV infection and disease. Environmental Co-factors for KSHV infection and disease Dr. Judy Mikovits and Dr. Bob Shoemaker of the NCI screening technologies branch, we have developed an in vitro KSHV activation assay. The assay uses real time PCR to measure virus reactivation in the latently infected primary effusion lymphoma (PEL) cell line BCP-1. We are using this assay to screen a natural products library for potential environmental co-factors for KSHV shedding, transmission and pathogenesis in collaboration with Dr. David Newman and Dr. Tom McCloud of the NCI natural products branch. The EPILYMPH study In collaboration with Dr. Silvia de SanjosU at the Department for Epidemiology and Cancer Registry, Institut CatalO dOncologia,t Barcelona, Spain, we are participating in a multicentric case control study of lymphoma in Europe co-ordinated by IARC. The study will examine the aetiology of haematological malignancies and we will lead the studies on KSHV.HTLV-1Aspects of HTLV-1 entry and tropism are being studied in collaboration with Dr. Kathy Jones in order to gain a greater understanding of the mechanisms of HTLV-1 transmission and pathogenesis. New VirusesStudies have been initiated to identify new oncogenic viruses using modern molecular techniques combined with insights from previous epidemiological studies.